I detailed out an alternative to buttermilk, but personally I think it adds a wonderful richness to the syrup that the milk-lemon juice combination just can't mimic. A little goes a long way with this syrup, so make a batch and keep it in a jar in the fridge for a month or two. I just pop the jar in the microwave for about a minute and we have delicious warm syrup on our pancakes and waffles.